Clutch Linkage for a Big Block

[ecgate]

Im wanting to know if the factory clutch linkage will work on a big block with headers. Im going to be swaping out my th400 and putting a tremec tko 5 speed and was wondering if the factory clutch linkage will work with headers or will I need to put a hydraulic clutch on it. I would prefer to use the clutch linkage if it wont interfere with anything.

[SS Tim]

My guess is that you are going to have problems.
Since you used chevelle headers it was not a consideration durng their manufacture.
http://67-72chevytrucks.com/vboard/s...0&postcount=19
At this point your best bet would be to get some parts and see if they fit.
As you won't be using the rear engine crossmember and bellhousing mounts there may be a little wiggle room to make it work.
Also is your engine in a stock location with the aftermarket stands or is that another issue to deal with too?

[imjeff]

Originally Posted by SS Tim

My guess is that you are going to have problems.
Since you used chevelle headers it was not a consideration durng their manufacture.

I have a chevelle with a big block and headers. I don't understand how it wasn't a consideration. I believe I had to order them with exactly that consideration. The clutch linkage indexes off the same boss regardless or chevelle or truck, doesn't it?

[SS Tim]

Originally Posted by imjeff

I have a chevelle with a big block and headers. I don't understand how it wasn't a consideration. I believe I had to order them with exactly that consideration. The clutch linkage indexes off the same boss regardless or chevelle or truck, doesn't it?

You took that out of context. The headers were not designed to clear a truck's clutch linkage, only for the specific factory chevelle installations intended for if even then.

Trucks keep the z bar a very specific location and use adapter plates to move the pivot ball location with some engine applications. IIRC the L6 and KE(V8) are the only direct to the block boss pivot balls.

When it comes down to it, he has non-truck specific headers and aftermarket mounts with an engine placed in a non-stock location.
So he is probably going to have to modify or mix and match to make it work.

[imjeff]

Originally Posted by SS Tim

You took that out of context. The headers were not designed to clear a truck's clutch linkage, only for the specific factory chevelle installations intended for if even then.

Trucks keep the z bar a very specific location and use adapter plates to move the pivot ball location with some engine applications. IIRC the L6 and KE(V8) are the only direct to the block boss pivot balls.

When it comes down to it, he has non-truck specific headers and aftermarket mounts with an engine placed in a non-stock location.
So he is probably going to have to modify or mix and match to make it work.

My bad, I guess. I didn't recall having the linkage offset from the ball on any of the swaps I've done. Granted, I've only swapped a half dozen big blocks into trucks and Chevelles so my recollection is probably off. Thought the z bars were pretty close.

Jeff

[ecgate]

Originally Posted by SS Tim

My guess is that you are going to have problems.
Since you used chevelle headers it was not a consideration durng their manufacture.
http://67-72chevytrucks.com/vboard/s...0&postcount=19
At this point your best bet would be to get some parts and see if they fit.
As you won't be using the rear engine crossmember and bellhousing mounts there may be a little wiggle room to make it work.
Also is your engine in a stock location with the aftermarket stands or is that another issue to deal with too?

Well that is where Im at right now. Im in the understanding that may be some issues but are they issues that can be worked around? Just wondering if someone out there has done this and if it works. My engine is not in the factory position because of the electric fan. It sits about an inch or inch and a half back.

[imjeff]

Originally Posted by ecgate

Well that is where Im at right now. Im in the understanding that may be some issues but are they issues that can be worked around? Just wondering if someone out there has done this and if it works. My engine is not in the factory position because of the electric fan. It sits about an inch or inch and a half back.

With as many variables as it sounds like you've got going on, I doubt anyone will be able to give you a for sure. Anything is workable. Steel can be cut, reshaped and welded back. Your fan shouldn't dictate engine location as electrics take less space than regular fans. You'll have to fit it up, see how things fit, hammer a little, maybe cut and fab a little, rinse, repeat. I've used Chevelle headers in Chevelles and pickup headers in pickups, but never even thought to try what you're up to so you might be out there all alone on this one. Good luck!

Jeff

[SS Tim]

Originally Posted by imjeff

With as many variables as it sounds like you've got going on, I doubt anyone will be able to give you a for sure. Anything is workable. Steel can be cut, reshaped and welded back. Your fan shouldn't dictate engine location as electrics take less space than regular fans. You'll have to fit it up, see how things fit, hammer a little, maybe cut and fab a little, rinse, repeat. I've used Chevelle headers in Chevelles and pickup headers in pickups, but never even thought to try what you're up to so you might be out there all alone on this one. Good luck!

Jeff

Well said! Still think at this point puting on a frame bracket and seeing where a stock a z-bar would land on the block or have to go around is the place to start.

[ecgate]

Ill figure it out one way or another but if someone out there has any recommendations Im all ears. I guess as of now I just need to get my hands on some factory linkage sets and see if I can piece it together and go from there and if I have to chop, bend, or weld something it isn't going to be the end of the world for me as long as it works.

[midniteblues]

i have nova/camaro headers installed on my 67 w a 454 they are close too a chevelle header if not the same. of course each differant brand of header is gonna be a lil' differnt.

i screwed the pivot ball into the block and relocated the mount on the frame.
uesing all factory clutch linkages i had too cut the top ear off of my z bar and made a slightly longer ear and rewelded it at a differnt angle and location on the z bar. but i didnt touch the bottom ear.
i had everything mocked up and it seemed too work ok but up untill i get the thing running and driveing i cant be 100% sure everything will be a-ok.
one differance is my bb is mounted in the factory front holes with oe style mounts. but i am useing a trans mounted crossmember.

idk how this will help you but i figured i say what i'd done

[southern parts]

original clutch linkage for a big block is super rare.

[midniteblues]

Originally Posted by southern parts

original clutch linkage for a big block is super rare.

sure is

[Tom Vogel]

I have a BB in my 2wd Jimmy (stock BB location). I am running a TKO 600 with stock BB clutch linkage. I have custom headers, however, I would think a set of standard long tubes would work ok because the collectors would hang down below the frame rail. My custom headers were built with the collectors up high for ground clearance, so the shape had to be engineered to clear the linkage, which is between the frame rails.. Which they do... At a cost$.

[imjeff]

The first one I did I used the stock SBC linkage. Drove that truck for many years without issue.

[southern parts]

how did you mount the pivot ball to the block ?

[imjeff]

Screwed it into the threaded hole on the block.